PP
Prototype. The first piece in the proofing period for a three-dimensional object that meets the aesthetic and technical approval of the artist and Gemini. Similar to a right to print impression, it is used as a guide for the production of the edition.

PAP
Presentation artist's proofs. A proof meeting the right to print impression or standard used for the edition that is intended for distribution to artists who contribute to a Gemini project. The impressions may be part of a portfolio or series to which a group of artists has contributed.

Paintstik
A drawing stick made from oil paint and other solid additives. Paintstiks can be mixed with turpentine or petroleum solvents. They may also be used for coloring prints or drawing images on printing elements.

patina
A sheen or coloration that signifies an object's age. Patina may appear on any surface as an unintentional effect or as an intentional, simulated product of aging. A primary definition refers to the green film forming on copper or bronze sculpture that may occur naturally (due to long exposure to the weather) or artificially (due to exposure to acid). Patina is often valued aesthetically for its color.

PC
Publisher's copy. The copy of a three-dimensional object, similar in nature to an artist's proof, which is retained by the publisher.

pewter
Any of various alloys having tin as its chief component.

photochemical (or photomechanical)
A term referring to the group of processes that allow a photographic image to be transferred to a printing element. This is frequently done by means of a dot screen through which the continuous gradations of photography are translated into spots of black and white.

photoengraving
A process for making relief plates by using acid to etch away the non-printing areas of a photographically produced image. The subject is photographed through a wire or glass screen, which breaks the light in a way that sensitizes the metal plate in a dotted pattern. Darker areas are created with larger dots while highlights are rendered with finer dots. When printed, the finest screens create the most precise detail. This process was used principally for reproducing illustrations in the earlier part of the 20th century.

photoetching
An intaglio process in which the etching plate is coated with a light-sensitive acid-resistant ground and exposed, through a dot screen, to a photographic image. A "negative" resist dissolves in the areas that are exposed to light, while hardening in areas not exposed to it. Thus pits are etched and ink is held in the areas that appear light in the photographic image. A positive resist dissolves where it is not exposed to light.

photogravure
A process using a bichromated gelatin tissue on a copper plate. The exposed and selectively hardened layer controls the penetration of an etching solution, so that the printing plate is etched to different depths. After inking, the plate is printed in the usual intaglio manner. See also gravure.

photolithography
A form of lithography in which light-sensitive plates or stones are exposed to a photographic image, usually by means of a halftone screen.

photo offset lithography
A printing process in which the image is photographically transferred to the stone or plate, which is then inked and indirectly transferred to an intermediary, such as a rubber cylinder on an offset press, which then transfers the inked image to the paper. Offset printing is primarily used for commercial purposes.

photoscreenprint
A form of screenprint in which a light-sensitive resist applied to the screen is exposed to a photographic image that has been broken down by a dot screen. Areas exposed to light harden. A photo stencil is created when unexposed sections, which are unaffected, are washed away. The ink is forced through the open mesh to create the image.

pochoir
French for "stencil." A direct method for hand-coloring prints with paints or inks applied through a stencil. The stencil is usually cut from paper, paperboard, plastic, or metal. Designs can also be chemically etched in thin metal to make the stencil.

PP
Progressive proof. A series of proofs intended to illustrate the image development of the completed print showing each color or element as added one by one.

PPII
Producer's proof II. A copy of a three-dimensional object that meets the prototype. It is generally presented to a fabricator who assisted in the proofing period and during production of the edition.

PR
Presentation proof. A proof meeting the right to print impression or standard used for the edition that is intended as a gift to a group or individual.

print
Prints are works of art produced in editions or multiple original impressions of the same image. They are made by transferring a layer of ink from a printing element, or matrix, onto paper or another material. A printing press frequently supplies the pressure for the transfer. The various printmaking techniques are defined by the type of matrix and the manner in which it carries ink. Complex color prints may call for several matrices, and more than one process may be used for a single print.

printing element
Any material, such as a stone, screen, or metal plate, upon which a design is created for the purpose of transfer. In prints involving more than one color, a separate printing element is usually drawn for each color. However, multiple colors may be simultaneously printed from a single element and elements may be used many times for different colors.

proof
Impressions pulled before the printing of the edition in which the development of the image is tracked and various inks, colors, papers, and other variables are tested.

pulp
Reduced fibers, often derived from cotton rags and linen, which are diluted with water to prepare for the formation of paper sheets.